Settings Reference

The same text as the Studio's extended tooltips (hold Ctrl+Alt over a control).

Parts

Pick Mode: Island

A click selects the whole connected piece under the cursor: every triangle that shares edges with it. Best for leaves, blades and props made of separate pieces. B switches between Island and Brush picking.

Pick Mode: Material

A click selects every triangle that uses the same material slot as the clicked one. Quick when trunk, branches and leaves already have their own materials.

Pick Mode: PolyGroup

A click selects the PolyGroup under the cursor. PolyGroups come from Modeling Mode or from the DCC export (face sets, smoothing groups).

Pick Mode: Triangle

Selects single triangles. Use it for small fixes on top of an island or material selection.

Pick Mode: Smooth (Angle)

Flood fill from the clicked triangle across neighbours whose normals differ by less than Angle (degrees). It selects one smooth surface and stops at hard edges. A larger Angle grows across sharper creases.

Pick Mode: Brush

Paints a selection onto the surface. Shift adds, Ctrl removes; Brush Radius sets its size. B switches between Brush and Island picking.

Pick Scope

Limits what a pick can select. Mesh: every visible triangle. Part: only triangles of the selected part. Free: only triangles that are not in any part yet.

Select Unassigned

Selects every triangle that is not in a part. Unassigned triangles never move in the wind, so check this before you build.

Attached + / Touch

Replaces the selection with the unassigned pieces that touch it, for example the leaves sitting on a selected branch. Touch is the distance (cm) under which two pieces count as touching.

Orphans

Selects bone-less pieces (leaves, decorations) whose pivot does not touch their parent surface. They are probably bound to the wrong branch: fix them with Follow, Add to Part or Attached +.

Hide / Isolate / Unhide

Hide (H) removes the selected triangles from the view; Isolate (I, Shift+H, Ctrl+1 or Num /) hides everything else; Unhide All (Alt+H or Ctrl+H) shows everything again. Hidden triangles cannot be picked.

New Part / Add / Remove

New Part moves the selected triangles out of their parts into a new one. Add to Part moves them into the selected part. Remove from Parts makes them unassigned: unassigned triangles never move in the wind.

Clear All Parts / Clear Rig

Removes every part and its bones (the root stays). Ctrl+Z undoes it, and Load Latest brings back the last autosave.

Auto-Split (Islands / Materials / PolyGroups)

Replaces all parts with one part per connected island, material slot or PolyGroup. Hold Shift to split only the selected triangles. On trees and bushes the largest part becomes Core (trunk) and the others start as Mid; other asset types start every part as Mid.

Part Role (Rigid / Core / Mid / Outer)

Rigid: locked to the root, never deforms. Core (Simulation Group 0): stiff trunk or base with a slow sway. Mid (Group 1): secondary branches and the body of cloth. Outer (Group 2): free tips, leaves and hanging elements. The role sets the bones' influence curve and the Epic Simulation Group they export to on the GPU tier.

Part Colour

Every new part gets the hue farthest from all other parts' colours, so two parts never share a colour. Click the swatch to pick any colour; Ctrl+Z undoes the change.

Follow

For bone-less geometry such as leaves. Pick the parent part: vertices of this part without bones of their own take weights only from that part's bones (closest bone line), never from the trunk or another branch.

Part Wind Scale

Scales the wind on this part: 1 = default, 0 = still, 2 = double.

Grass Clumps (W / Wd / S)

Needs Follow. Each bone-less blade binds to one chain of the followed part and bends along it, so a few chains drive a dense patch. W: per-blade variation of the bend curve and root share (0-1). Wd: per-chain wind variation of the followed part (up to +/-50 % at 1). S: random seed.

Attached End

Marks which side of the piece is attached; auto chains start there and grow towards the free end. Click to toggle.

Edit Pivot (P)

Drag the pivot gizmo or click the surface to place a new pivot, then Apply (Enter) to bake it into all LODs and collision; bones shift with it. Esc or Cancel reverts to the asset's pivot.

Pivot Snaps

Snap the pending pivot to the bottom centre (trees, standing props), top centre (banners, lamps, vines), box centre, the triangle selection or the selected bone. Apply Pivot bakes it.

Mesh Scale

Scale factors around the pivot (1 = unchanged). Apply Scale bakes them into the Static Mesh (all LODs, Nanite source, sockets, collision), scales the bones with it and resets the transform to 1.

Bones

Auto Bones: Fit

Auto (Adaptive): branching for 3D structures, parallel chains for flat cloth. Chains: straight chains for flags, ropes and stems. Branching: a forking skeleton for trees.

Bone Style (Spacing / Absolute)

Spacing: one bone every Bone Spacing along each chain, the same density over the whole mesh (a 5 m branch gets five times the bones of a 1 m branch). Absolute: every chain gets the same number of bones.

Bone Spacing / Max Bones Per Chain

Distance between bones along each chain (default 20 cm, about the spacing of Epic's PVE trees). Epic's GPU wind bends at every joint, so sparse chains move less and look stiffer. Max Bones Per Chain caps very long chains.

Resample All Chains to Spacing

Re-samples every trunk, branch and side branch of the current rig to one bone every Bone Spacing along its curve. Branches on them are re-parented and paint layers move to the nearest new bone. Ctrl+Z undoes it.

Auto Bones: Selected Part / All Parts

Fits bone chains to the selected part with the generator settings; running it again replaces that part's previous auto bones. All Parts works on Core parts first, then Mid, then Outer, so outer chains can hang from inner ones.

Clear Bones of Part

Deletes all bones bound to the selected part. The part itself stays.

Re-parent

Moves the selected bones under a new parent (To Root: under the root). Positions stay; only the hierarchy changes.

Root to 0,0,0

Moves the root bone to the origin. Other bones stay where they are. Ctrl+Z undoes it.

Weld

Merges the selected bones into one (or a single bone into its parent): skin weights are combined and children are re-parented.

Straighten

Places the bones between the first and the last selected bone evenly on a straight line.

Insert Before

Splits the segment between the selected bone and its parent with a new bone.

Chain Bones - / +

One bone less or more on the selected trunk or branch (the selected bone's chain, or the chain nearest the triangle selection). The chain is re-sampled along its curve and branches on it are re-parented to the nearest bone.

Snap Bone

Moves the selected bone to the centre or one side (-X, +X, -Y, +Y, bottom, top) of the triangle selection or the selected part. Children follow when Move Children with Bone is on; Shift inverts that for one move.

Delete Bones

Delete (Del): removes the selected bone and re-parents its children. Del + Children: removes the bone and everything below it. Delete All Bones: removes the whole skeleton; parts stay. Ctrl+Z undoes all of them.

Wind Weight: Static / Max / Auto

Wind weight of the selected bones: 0 = completely still, 1 = full wind. Auto goes back to the automatic weight from the bone's depth and its group's influence curve. [ and ] nudge the weight in small steps.

Wind Weight: Ramp / Arch

Ramp 0 -> 1: weights rise linearly from the first selected bone to the last (stems, branches, banners). Arch 0 -> 1 -> 0: both ends still, full weight in the middle (cables, ropes, hammocks).

Match Same Level

Bones at the same depth (for example every _03 bone of a banner) get the mean of their current wind weights. Works on the selected bones, or on all bones when none is selected.

Randomize Wind Weight

Adds a random variation of +/- Amount to the wind weight of the selected bones (all bones when none is selected). 0.15 = up to +/-15 %. Static bones stay static; every click gives a new variation.

Reset Wind Weights

Selected or all bones go back to the automatic wind weight from the Influence Curves, removing manual Wind Weights. Ctrl+Z undoes it.

Reset Curves & GPU Groups

Influence Curves, GPU Simulation Groups, Gust Attenuation and Ground Cover go back to the defaults of the asset type. Bone Wind Weights are kept. Ctrl+Z undoes it.

Skin Weight Scale

Scales how strongly the selected bones pull on every vertex they move (-25 %, -10 %, +10 %, +25 %). The other bones on those vertices take the rest, so weights stay normalised.

Paint Weights (R)

Paints skin weight for the selected bone, or Pin (stillness), onto the mesh. Modes: Add, Subtract, Smooth, Set Value. While painting, Shift smooths and Ctrl inverts Add / Subtract. [ / ] change the radius, Shift+[ / Shift+] the strength. Only Paint Inside Selected Part keeps the brush on one part. Right-click the Paint Weights button to open the SKIN WEIGHTS window (brush settings); R and left-click only switch to the tool.

Paint Target: Pin (Stillness)

Paints rigidity anchored to the root: pinned vertices stay still whatever their bones do. Use it on the base of a plant, the pole edge of a flag or the fixed ends of a cable.

Apply to Selection / Value

Sets the paint target to Value on every selected triangle at once. Value is also the target of the Set Value brush mode.

Smooth Weights

Each click runs one smoothing pass over all skin weights (like Blender's Smooth Vertex Weights). Rigid parts stay locked. Reset Smoothing removes all passes.

Cloth Grid Skinning

For banners, curtains and flags on CPU Physics: each vertex blends the two neighbouring chains and the two nearest bones along them, so the cloth stays one smooth sheet. Off: distance blend with Skin Blend Width.

Skin Blend Width

Width of the soft skin blend between bones (GPU tier, and cloth with Cloth Grid Skinning off). Larger = smoother, softer bends; smaller = tighter to each bone.

Wind

Asset Type

What the asset is (tree, bush, ground cover, banner, flag, cable...). Choosing a type applies its default influence curves and motion. Tree and Bush export Core bones as trunk bones; all other types export without trunk and without height attenuation.

Runtime Tier

How placed copies animate. GPU: Epic Dynamic Wind on a Nanite skinned mesh, cheapest for large amounts of foliage. Pivot Paint: a Static Mesh with Pivot Painter 2 data animated in the material (MF_CAAPivotPaint), also for foliage instancing. CPU Physics: the plugin's bone chain solver for hero assets and character contact. A placed actor can override the tier on its CAA Wind Driver component.

Wind Preset

How this kind of plant or object moves from calm to storm (bend, swing, frequency, waves to the tip and independence for each level). Choosing a preset resets the scales below to 1; Reset Motion to Type Defaults restores the asset type's motion. The Motion card drives Pivot Paint and the CPU tree mode, never the GPU tier.

Motion: Bend

How far the asset leans downwind. At the maximum it leans 90 degrees in a storm.

Motion: Turbulence

How much it swings around the lean. At the maximum it swings 90 degrees in a storm.

Motion: Speed

How fast it swings (natural frequency), from 0.02 Hz to 10 Hz. Very high values alias at 30 fps.

Motion: Flexibility

Waves running from the base to the tip. 0 = bends as one stiff piece; the maximum puts the tip 3/4 of a swing behind the base. CPU Physics keeps a short motion history, so on slow trunks values above about 0.56 change nothing more.

Motion: Independence

0 = all branches move together; the maximum gives each its own fully random phase.

Two-Pinned Cable Rig

Rigs the selected part (or all unassigned triangles) as a cable fixed at both ends: two anchors and two mirrored chains meeting at mid-span, which works with Epic's single-root GPU wind. Weld Touching Tips joins the two chain tips into one rope on the CPU tier.

Fabric

Weight of the cloth: 0 = silk or a thin dress (light, quick ripples), 0.33 = cotton, 0.67 = canvas or tarp, 1 = a wet towel (heavy, hangs, moves slowly).

Pivot Paint: Max Elements

Pivot Painter 2 elements of the build: each moving chain and each leaf piece is one. 30,719 is the Pivot Painter 2 maximum; fewer elements mean smaller textures and more grouped leaves.

Pivot Paint: Leaf Grouping

When the element budget is reached, leaves are grouped. Group Hidden Leaves First 0 = grouped evenly everywhere; 1 = leaves inside and low in the plant are grouped first, the outer crown keeps its own leaves the longest. Hidden: Inside / Low decides what counts as hidden: 0 = near the vertical axis, 1 = low in the plant, 0.5 = both.

CPU Physics Defaults

Restores every CPU Physics setting to the defaults of the current asset type.

Wind Drag / Edge-on Drag

Wind Drag (1/s): how fast bones take on the wind's velocity; higher = lighter material. Edge-on Drag: drag along a surface or rope relative to drag across it.

Wind Speed Scale

Multiplies the level wind speed (km/h) for this asset only.

Turbulence / Turbulence Size

Gusty, swirling air relative to the mean wind, and the size (cm) of the travelling turbulence cells.

Flutter

A travelling flap wave on free bones, relative to the wind push. Frequency is given at 30 km/h and scales with wind speed; Wavelength is the length of one wave along the wind.

Gravity Scale

1 = real gravity (cloth, ropes). 0 for plants that keep their modelled shape.

Shape Stiffness / Damping

A spring (Hz) that keeps free bones in their modelled shape: 0 = limp, 1-2 = branches. Low-influence bones are stiffer. Shape Damping is the damping ratio of that spring.

Air Damping

Extra damping (1/s) on top of the wind drag. Raise it to calm down jittery or over-swinging bones.

Inertia

1 = free bones trail behind when the actor moves; 0 = they move rigidly with it.

Cloth Links

Links neighbouring chains at the same height so a banner keeps its width and catches the wind as one surface. Bend Stiffness resists folding across the sheet (0 = off). Fold Limit keeps each bone at least that fraction of its rest distance from its grandparent (0.7 = bends up to about 90 degrees, 0 = no limit).

GPU Group: Trunk

Exports the group as Epic's trunk group: a slow whole-plant sway instead of branch motion.

GPU Group Influence

How strongly Epic's GPU wind moves this group (0 = still, 1 = full). With Dual Influence the value ramps from Min at the base to Max at the tip of each chain; Shift Top is the part of the chain that stays at Min before the ramp starts.

Gust Attenuation / Sync from Source

Gust Attenuation damps gusts on this mesh (Epic's setting). Sync Wind from Source Mesh reads the source mesh's Epic Dynamic Wind data (ground cover, gust attenuation, group influences) into these settings; the GPU build writes them back.

Simulate Wind (Space)

Plays the wind preview of the chosen runtime tier. GPU: Epic's Dynamic Wind on a Nanite copy of the mesh, as in the level; GPU group edits apply live, a rig change needs a new Simulate Wind (the Nanite build can take about 15 s on big trees). Pivot Paint: the Pivot Painter 2 preview. CPU Physics: the same solver as placed actors. In the Weights and Wind views the GPU tier shows a coloured CPU twin of Epic's motion. Space or Alt+V toggles it. Needs at least two bones.

Preview Wind Speed

Preview wind speed in km/h, the same unit as the Level Wind Manager (Breeze 15, Strong 35, Storm 65, Gale 95). CPU Physics and Pivot Paint react to speed.

Preview GPU in Level

Builds the mesh and places it in the level with Epic's GPU wind, driven by the level's Wind Manager.

Interaction

Block Characters

On: the plant's collision stops characters. Off (default, plants): pawns and the camera pass through and push it aside. Stored on the built asset.

Push Radius

Radius of the push around a player pawn that has no CAA Wind Interaction component. With the component, its Interaction Radius is used.

Trunk Strength

Multiplier on the automatic trunk strength from the plant's height: 30 cm or less = a soft stem that bends from its base, 3 m or more = a tree trunk that sways a little and is not bent by characters.

Push Bend

Bend (degrees) applied by characters and CAA Wind Interaction components.

Contact Bend / Max Contact Bend

CPU Physics: how strongly a character capsule bends the branches it touches (1 = default), and the most it can bend one.

Collide with Characters

CPU Physics: player pawns and actors with a CAA Wind Interaction component push the bones out of their capsule.

Test Character

A 180 cm capsule walks back and forth through the plant while Simulate Wind runs, to judge the push in the CPU Physics and Pivot Paint previews.

Build

Destination Folder

Content folder the built Skeletal Mesh, Skeleton and Physics Asset are saved to.

Asset Name / Replace Existing

Palm01 builds SK_Palm01, SKEL_Palm01 and PHYS_Palm01. Replace Existing rebuilds into those assets so placed actors keep working; off creates numbered copies.

Save / Load Rig

Saves parts, bones, paint and wind settings to a .json file, or loads one. The mesh must have the same triangle count.

Autosave (Ctrl+S)

The rig is autosaved 3 s after every edit; Ctrl+S saves it immediately. Load Latest brings that file back, also after the rig was cleared. Ctrl+Z undoes the load.

Build Skeletal Mesh (F7)

Builds the Skeletal Mesh, Skeleton and, when enabled, the Physics Asset. Rebuilding an existing asset replaces it in place; render objects pause for a moment during the swap so Epic's Dynamic Wind never reads a half-built mesh.

Place in Level

Places the built mesh in front of the level camera with its runtime tier: GPU = Instanced Skinned Mesh with Epic's Dynamic Wind provider (needs Nanite), Pivot Paint = Static Mesh with MF_CAAPivotPaint, CPU Physics = Skeletal Mesh with the CAA wind animation.

Level Wind Manager

Finds or spawns the CAA Wind Manager of the level. It drives Epic's GPU wind, the CPU solver and MPC_GlobalWind (wind values and character push).

Auto Rig + Build

One click: splits the mesh by islands (only if it has no parts), generates bones for all parts (only if it has no bones), then builds.

Validate Rig

Runs the export checks without building. The full report goes to the Export section.

Build Pivot Paint Mesh

Builds SM_<Name>_PivotPaint (a Static Mesh, also for foliage instancing), its two Pivot Painter 2 textures (each chain and each leaf island is an element) and one material instance per slot. The data is 100 % compatible with Epic's Pivot Painter 2.

Export Wind Data (JSON + USD)

Writes <Mesh>.DynamicWind.json (Epic's Import Dynamic Wind format) and <Mesh>.DynamicWind.usda (UsdSkel skeleton with DynamicWindSkeletonAPI, for Nanite Assembly) to Saved/WindStudioExports or a folder you pick.

Optimization: Reduce Bones

CPU Physics only, off by default. Builds from a copy of the rig with one bone every N cm along each trunk, branch and side branch: fewer bones mean a cheaper solver, bone upload and skinning. Short twigs keep their start and end. The Studio rig itself is not changed.

Optimization: Limit Bones per Vertex

Keeps only the strongest 1-4 bones per vertex and re-normalises: cheaper skinning. 1 = rigid pieces; 2 is usually invisible on leaves and twigs.

Optimization: No Physics Asset

With Block Characters off the wind reaches characters through its own capsules, so the mesh can be built without a Physics Asset (no bodies to register or move). Ignored when Block Characters is on.

Optimization: Distance LOD

Stored in the mesh: placed copies farther than N m from the camera solve the wind every 2nd frame, beyond 2N m every 4th frame.

Physics Body Shape

Capsules suit branches, trunks and ropes, boxes suit flags and banners, spheres are the cheapest and suit leaves.

Physics Asset

Generates collision bodies for the last built mesh with these settings. Create with Mesh does it on every build.

View

Tools

Select (V): pick triangles, islands or brush regions; drag on empty space for a box selection; double-click a part to select all of it. Move (T): drag bones or the root with the gizmo. Place Bones (J): click the surface to add bones. Paint Weights (R) and Edit Pivot (P) are described in their own entries.

Display Modes

Lit (Alt+1 or 6): materials and lighting. Parts (Alt+2): part colours. Clay (Alt+3 or 5): neutral grey. Weights (Alt+4): skin weight heatmap. Wind (Alt+5): wind influence heatmap, from dark blue (still) to red (full).

Anti-Aliasing / Resolution

FXAA (default) leaves no trails behind moving leaves; TAA and TSR blend earlier frames, so the moving wind preview smears. Resolution above 100 % renders the frame larger and scales it down (default 200 %): smooth edges with no smearing. Lower it if the viewport gets slow.

Lines & Gizmos

Thickness and size of bone lines, joints, bone axes, grid lines, gizmos and the wind arrow. Defaults: Bone Lines 0.4, Joint Size 0.4, Axis Line Size 1.0, Grid Lines 0.1, Grid Visibility 1.0, Gizmo Lines 0.2, Gizmo Size 0.5, Wind Arrow Lines 0.4, Wind Arrow Size 0.6. Saved per project.

Show Helpers (G)

Turns the grid, bones, bone axes and wind arrow on or off one by one. G hides or shows all viewport helpers at once, like Unreal's Game View.

Ground Grid

Cell spacing (default 0.5 m), visibility (default 1.0) and line thickness (default 0.1) of the floor grid. Snap Z puts the grid at the lowest vertex instead of Z = 0; Center XY centres it under the mesh instead of the world origin.

Scale Ruler & Mannequin

Measured ruler lines along the chosen axes (X, Y and Z by default), drawn just outside the mesh bounds. An optional 180 cm figure can stand beside the mesh for scale.

Backdrop & Lights

The Backdrop button switches between the neutral studio and the dark CAD backdrop and resets the lights to that preset. Custom Background and Override Lights use the values in the VIEW window instead. Reset restores all view defaults.

Two-Sided Shading

Renders both sides of every face in the viewport, for flags, foliage and single-sided cloth.

Camera

F frames the selection (the whole mesh when nothing is selected), Home frames the whole mesh. Reset 3D returns to the default 3/4 view; Top, Front and Side look along -Z, +Y and +X. Unreal's navigation is unchanged: RMB + W A S D Q E to fly, Alt + mouse to orbit, dolly and pan, MMB to pan.